Atherosclerotic intracranial artery stenosis is a common etiology for ischemic stroke and TIA in Japan with annual stroke rates that approximate 5% to 10%. There are no conclusive answers about the best medical treatment for intracranial stenosis. Recently, the efficacy of dual antiplatelet therapy has been reported. In the SAMMPRIS study, aggressive medical management was superior to balloon angioplasty/stenting with the use of the Wingspan stent system and the 30-day rate of stroke or death was 14.7% in the endovascular group and 5.8% in the medical-management group.

  The Wingspan stent system was approved in Japan in 2014. The indications of use for the Wingspan system are as follows, 1) dissection, acute occlusion, and impending occlusion after balloon angioplasty, 2) restenosis after balloon angioplasty without any other additional effective treatment. The endovascular treatment for intracranial artery stenosis with the Wingspan stent system has been reported to have a relatively high incidence of ischemic and hemorrhagic complications. However, endovascular treatment via angioplasty without stenting is a relatively low invasive technique with a relatively low rate of technical complications and its effectiveness has been well demonstrated.

  As the recanalization rate has been remarkably improved by the development of the stent retriever, shortening therapeutic time has become a key factor determining the patients’ prognosis. Among all procedures, reducing door to puncture time depends heavily on the quality of cooperation between all stroke team members : doctors and co-medical staff. Requirements to strengthen the stroke team are (1) doctor’s leadership, (2) regular communication among all divisions, and (3) making use of past clinical experience. It is important for doctors to educate and build a cooperative relationship with co-medical staffs, in order to shorten therapeutic time.

  Carotid artery stenting (CAS) is an alternative to carotid endarterectomy (CEA) that promises long-term efficacy. Patients indicated for carotid revascularization often have systemic atherosclerotic disease, therefore CAS has advantage in its ability to reduce periprocedural systemic complications including myocardial infarction via its less invasiveness. However, recent large randomized control trials have revealed that CAS has a higher potential risk of periprocedural ischemic stroke. The main factors likely to participate this event are incomplete embolic protection during balloon or stent angioplasty, and post-procedural thrombus that emerges on the stented area associate to the protrusion material through the bare metal stent. In this article, we present an outline of the recent randomized control trials, SPACE, EVA-3S, ICSS, CREST and ACT-1, and focus on the cerebral ischemic complications in these trials, and describe in detail of the mechanism of periprocedural thromboembolic events and their countermeasures.

  Reducing of periprocedural ischemic complication is the task to date, and active utilization of proximal balloon embolic protection to unstable plaque on tailor-made manner and newly developed micro mesh-covered stent may affect the efficacy of CAS as we go forward.

  Carotid endarterectomy (CEA) is the gold standard of surgical treatment for symptomatic or asymptomatic carotid stenosis. Mastering the CEA procedure is important for neurosurgeons because they gain the skill to extract plaque when it is vulnerable or high in volume in particular. In this article, we describe the basic procedure of CEA and its variations.

  When we perform CEA, it is important to keep a bloodless surgical field, peel off the internal carotid artery enough to expose an area distal to the plaque and extract the plaque stump surely.

  As variations of CEA, we describe emergent CEA, CEA for radiation induced carotid stenosis and hybrid operations. In all cases, we must perform the procedure with rigorous care to avoid perioperative complications.

  We report a case of epidermoid cyst that manifested with unusual radiological findings. A 32-year-old man felt dizzy and a CT scan revealed an extra axial lesion in the front of the left cerebellopontine angle to the medulla oblongata. The lesion showed as hyperdense on CT scan, hyperintense on T1-weighted imaging, and hypointense on T2-weighted imaging. The lesion also showed hypointense on diffusion-weighted imaging. We considered that it contained magnetic resonance and made a preoperative diagnosis of melanocytoma. After surgery, it was confirmed to be an epidermoid cyst. Histological examination found no evidence of either melanin or hemosiderin.

  Typicaly, epidermoid cysts’ radiological findings show as a hypodense mass on CT scan, hypointense on T1-weighted imaging, and hyperintense on T2-weighted imaging and diffusion-weighted imaging. But MR imaging signal intensity of epidermoid cysts is varied depending on the protein concentration and the presence of hemorrhage. Owing to those cases where an epidermoid cyst manifests unusual radiological findings, we must always list it as a possible diagnose for an extra axial mass.

  Concurrent spinal tumors such as schwannomas and meningiomas are usually associated with neurofibromatosis type 2 (NF2). Here we report an extremely rare case of concurrent schwannoma and meningioma at the same cervical spinal level. This patient did not meet the diagnostic criteria for NF2. Because the surgical strategy for spinal schwannomas may differ if meningiomas are concurrently present, it is important to pay attention to preoperative imaging findings. Unlike in previous patients, however, it was difficult to diagnose the presence of two different tumors based on preoperative images of the present patient. Preoperative images and intraoperative findings must therefore be carefully assessed to determine whether spinal tumors extending into the intradural and extradural spaces consist of concurrent schwannomas and meningiomas.